/*
 * Copyright (C) 2001-2010 Jacek Sieka, arnetheduck on gmail point com
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#if !defined(SINGLE_INSTANCE_H)
#define SINGLE_INSTANCE_H

#define WMU_WHERE_ARE_YOU_MSG _T("WMU_WHERE_ARE_YOU-{885D4B75-6606-4add-A8DE-EEEDC04181F1}")
const UINT WMU_WHERE_ARE_YOU = ::RegisterWindowMessage(_T("WMU_WHERE_ARE_YOU_MSG"));

class SingleInstance
{
		DWORD  LastError;
		HANDLE hMutex;
		
	public:
		SingleInstance(const TCHAR* strMutexName)
		{
			// strMutexName must be unique
			hMutex = CreateMutex(NULL, FALSE, strMutexName);
			LastError = GetLastError();
		}
		
		~SingleInstance()
		{
			if (hMutex)
			{
				CloseHandle(hMutex);
				hMutex = NULL;
			}
		}
		
		BOOL IsAnotherInstanceRunning()
		{
			return (ERROR_ALREADY_EXISTS == LastError);
		}
};

#endif // !defined(SINGLE_INSTANCE_H)

/**
 * @file
 * $Id: SingleInstance.h 6715 2011-04-01 22:57:43Z sa.stolper $
 */
